Prior-art guided missiles require for their flight guidance and self-guiding so-called inertial platforms, which are able to determine electrically processable values of changes in the roll angle, pitch angle and yaw angle in space. In addition, the inertial platform generally also determines acceleration values in the three body axes, from which the onboard computer is able to infer changes in flight velocity by integration. However, the onboard computer does not receive data on the absolute position in space, nor on the three velocity vectors.
The Polaris rockets according to U.S. Pat. No. 4,470,562 also contain such an inertial platform, but they are suitable only for underwater launching.
In air-to-ground systems known hitherto, the missile receives the missing data during carrier flight (as it is carried by a carrier plane) from the carrier plane by data transmission via an electrical interface. Planes which are not equipped with such an interface were therefore unable to be used for launching guided missiles.
Further, it has been known to be a problem with air to ground systems wherein the missile is activated at a late stage during fight. For example, pilots often hesitate to activate a missile prior to launch (arm the missile which basically amounts to providing power and data to the missile). However, if a missile is armed just 20 seconds prior to its use, there will not be enough time (or movement of the plane) to update the guidance system of the missile as the data transmission via the electrical interface is often used to recalibrate the various guidance sensors. If the missile is armed during level and stable flight, the data transmission via the electrical interface will not necessarily update and recalibrate to a great enough extent because of the stable and level flight.